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Quadrilateral cell-Based Anisotropic Adaptive Solution for the Euler Equations

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communications in computational Physics 2011年第1期9卷 68-88页

作者： H.W.Zheng n.Qin f.c.G.A.nicolleau c.Shu Department of Mechanical Engineering University of SheffieldMappin StreetSheffield S13JDUK Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260.

An anisotropic solution adaptive method based on unstructured quadrilateral meshes for inviscid compressible flows is *** data structure,the directional refinement and coarsening,including the method for initializing the refined new cells,for the anisotropic adaptive method are *** provides efficient high resolution of flow features,which are aligned with the original quadrilateral mesh *** different cases are provided to show that it could be used to resolve the anisotropic flow features and be applied to model the complex geometry as well as to keep a relative high order of accuracy on an efficient anisotropic mesh.

关键词： Anisotropic adaptive mesh refinement quadrilateral mesh finite volume face-based algorithm HLLc Euler equation

Improvements in tribological and anticorrosion performance of porous Ti–6Al–4V via PEO coating

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friction 2021年第5期9卷 1303-1318页

作者： c.Garcia-cabezón M.L.Rodríguez-Méndez V.AmigóBorrás R.Bayón c.Salvo-comino c.Garcia-Hernandez f.Martin-Pedrosa Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain BioecoUVA Research Institute Universidad de ValladolidValladolid 47011Spain Group UVASEnS Escuela de Ingenierías IndustrialesUniversidad de ValladolidValladolid 47011Spain Instituto de Tecnología de Materials Univesitat Politécnica de ValenciaValencia 46022Spain Tribology Unit Fundación IK4-TeknikerEibar 20600Spain

Medical implants manufactured using biomaterial Ti–6Al–4V exhibit some *** higher elastic modulus than that of natural bone can cause stress shielding *** can be avoided using Ti–6Al–4V with pores in the implant ***,poor corrosion and tribocorrosion behaviors are yielded because of the large area exposed to the *** mitigate both issues,coating technologies can be *** plasma electrolytic oxidation(PEO)process is a cost‐effective process that has been used successfully in nonporous Ti *** this study,two PEO coatings with different amounts of ca/P are ***,reports regarding their application in porous materials are *** effects of PEO treatments on corrosion and tribocorrosion in Ti–6Al–4V powder metallurgy are analyzed *** porous materials provide an efficient surface for PEO coatings,as demonstrated via scanning electron microscopy(SEM)and atomic force microscopy(AfM),and the porosity of the substrates improved the adherence of the *** corrosion resistance measured via electrochemical impedance spectroscopy confirmed the beneficial effect of the coatings,particularly for long exposure *** lower roughness,small pore size,and more compact film observed in the PEO–ca/P sample resulted in favorable tribological and corrosion properties.

关键词： Ti‐based alloys corrosion tribocorrosion surface modification

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： n c ROY M R TALUKDER A n chOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(ROS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Shape of the geometrically active atomic states of carbon

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chinese Physics B 2010年第2期19卷 219-224页

作者：熊庄 Bacalis n.c. AMS Research center Southeast University Theoretical and Physical chemistry Institute National Hellenic Research FoundationVasileos Constantinou 48AthensGreece 11635

We have developed a computer code for {／em ab initio} the variational configuration interaction calculation of the electronic structure of atoms via variationally optimized Lagurre type orbitals, treating the orbital effective charges as variational parameters. Excited states of the same symmetry, in order to avoid the inherent restrictions of the standard method of Hylleraas--Unheim and MacDonald, are computed variationally by minimizing the recently developed minimization functionals for excited states. By computing, at the minimum, the one-electron density and the probability distribution of the two-electron angle, and the most probable two-electron angle, we investigate the atomic states of the carbon atom. We show that, without resorting to the （admittedly unproven） concept of hybridization, as an intrinsic property of the atomic wave function, the most probable value of the two-electron angle is around the known angles of carbon bonding, i.e. either 109^／circ or 120^／circ or 180^／circ, depending on each low-lying state of the bare carbon atom.

关键词： carbon hybridization excited states variational principle

Regularized quantile regression for SnP marker estimation of pig growth curves

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Journal of Animal Science and Biotechnology 2017年第4期8卷 824-832页

作者： L.M.A.Barroso M.nascimento A.c.c.nascimento1 f.f.Silva n.V.L.Serao c.D.cruz M.D.V.Resende f.L.Silva c.f.Azevedo P.S.Lopes S.E.f.Guimaraes Department of Statistics Federal University of Vicosa Av. P H Rolfs s/nUniversity Campus Vicosa MG 36570-000 Brazil Department of Animal Science Federal University of Vicosa Av. P H Rolfs s/n University CampusVicosa MG 36570-000 Brazil Department of Animal Science Iowa State University Kildee Hall 50011 Ames Iowa USA Department of General Biology Federal University of Vicosa Av. P H Rolfs s/n University CampusVicosa MG 36570-000 Brazil Embrapa forestry Estrada da Ribeira km 111Colombo PR Brazil. Department of Plant Science Federal University of Vicosa Av. P H Rolfs s/n University Campus Vicosa MG 36570-000 Brazil

Background: Genomic growth curves are general y defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression(QR). This methodology allows for the estimation of marker effects at different levels of the variable of interest. We aimed to propose and evaluate a regularized quantile regression for SnP marker effect estimation of pig growth curves, as well as to identify the chromosome regions of the most relevant markers and to estimate the genetic individual weight trajectory over time(genomic growth curve) under different quantiles(levels).Results: The regularized quantile regression(RQR) enabled the discovery, at different levels of interest(quantiles), of the most relevant markers al owing for the identification of QTL regions. We found the same relevant markers simultaneously affecting different growth curve parameters(mature weight and maturity rate): two(ALGA0096701 and ALGA0029483)for RQR(0.2), one(ALGA0096701) for RQR(0.5), and one(ALGA0003761) for RQR(0.8). Three average genomic growth curves were obtained and the behavior was explained by the curve in quantile 0.2, which differed from the ***: RQR allowed for the construction of genomic growth curves, which is the key to identifying and selecting the most desirable animals for breeding purposes. furthermore, the proposed model enabled us to find, at different levels of interest(quantiles), the most relevant markers for each trait(growth curve parameter estimates) and their respective chromosomal positions(identification of new QTL regions for growth curves in pigs). These markers can be exploited under the context of marker assisted selection while aiming to change the shape of pig growth curves.

关键词： Genome association Growth curve Pig QTL Regularized quantile regression

A mixed problem of plate bending for doubly connected domains with partially unknown boundaries in the presence of cyclic symmetry

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Science china(Physics,Mechanics & Astronomy) 2010年第10期53卷 1884-1894页

作者： Odishelidze n criado-Aldeanueva f faculty of Exact and natural Sciences Tbilisi State University Department of Applied Physics II University of Malaga

This paper addresses the problem of plate bending for a doubly connected body with outer and inner boundaries in the form of regular polygons with a common center and parallel *** neighborhoods of the vertices of the inner boundary are equal full-strength smooth arcs symmetric about the rays coming from the vertices to the center,but have unknown *** bars are attached to the linear parts of the *** plate bends by the moments applied to the middle point *** unknown arcs are free from external *** same problem of plate bending is considered for a regular hexagon weakened by a full-strength *** the methods of complex analysis,the analytical image of Kolosov-Muskhelishvili's complex potentials (characterizing an elastic equilibrium of the body),the plate deflection and unknown parts of its boundary are determined under the condition that the tangential normal moment on that plate takes a constant *** analyses are also performed and the corresponding graphs are constructed.

关键词： plate bending theory complex variable.

Adrenomedullin in cirrhotic and non-cirrhotic portal hypertension

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World Journal of Gastroenterology 2003年第10期9卷 2325-2327页

作者： V Tahan E Avsar c Karaca E Uslu f Eren S Aydin H Uzun HO Hamzaoglu f Besisik c Kalayci A Okten n Tozun Gastroenterology Institute Marmara University Gastroenterology Department Medical faculty Istanbul University Biochemistry Department Cerrahpasa Medical FacultyIstanbul University

AIM:Adrenomedullin (ADM) is a potent vasodilator peptide. ADM and nitric oxide (nO) are produced in vascular endothelial *** ADM level has been linked to hyperdynamic circulation and arterial vasodilatation in cirrhotic portal hypertension (cPH).The role of ADM in non-cirrhotic portal hypertension (ncPH) is unknown,plasma ADM levels were studied in patients with ncPH,compensated and decompensated cirrhosis in order to determine its contribution to portal hypertension (PH) in these groups. METHODS:There were 4 groups of *** 1 consisted of 27 patients (f/M:12/15) with ncPH due to portal and/or splenic vein thrombosis (mean age:41±12 years),group 2 consisted of 14 patients (f/M:6/8) with compensated (child-Pugh A) cirrhosis (mean age:46±4), group 3 consisted of 16 patients (f/M:6/10) with decompensated (child-Pugh c) cirrhosis (mean age:47±12). fourteen healthy subjects (f/M:6/8) (mean age:44±8) were used as controls in Group *** level was measured by *** was determined as nitrite/nitrate level by chemoluminescence. RESULTS:ADM level in Group 1 (236±61.4 pg/mL) was significantly higher than that in group 2 (108.4±28.3 pg/mL) and group 4 (84.1±31.5 pg/mL) (both Pn that in Group3 (324±93.7 pg/mL) (P=0.002).nO level in group 1 (27±1.4 μmol/L) was significantly higher than that in group 2 (19.8±2.8 μmol/L) and group 4 (16.9±1.6 μmol/L) but was lower than that in Group 3 (39±3.6 μmol/L) (for all three Png correlation was observed between ADM and nO levels (r=0.827,PcOncLUSIOn:Adrenomedullin and nO levels were high in both non-cirrhotic and cirrhotic portal hypertension and were closely correlated,Adrenomedullin and nO levels increased proportionally with the severity of cirrhosis,and were significantly higher than those in patients with ncPH. Portal hypertension plays an important role in the increase of ADM and *** damage in cirrhosis may contribute to the increase in these paramete

关键词： Adult comparative Study female Humans Hypertension, Portal Liver cirrhosis Male Middle Aged nitrates nitric Oxide nitrites Peptides Vasodilation

Degradation of Methylene Blue and Rhodamine B Using a new Visible Light-Responsive Photocatalyst, KSb_2PO_(8-x)n_y

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Acta Metallurgica Sinica(English Letters) 2016年第4期29卷 335-343页

作者： G.Ravi ch.Sudhakar Reddy K.Sreenu Ravinder Guje Radha Velchuri M.Vithal Department of chemistry University College of ScienceOsmania University

Potassium phosphatoantimonates, KSb2PO8 （KSbPO） and KSb2PO8-xny （KSbPOn）, are prepared by solidstate method. Urea is employed as a source of nitrogen for n-doping. Structural, morphological and optical properties of both KSbPO and KSbPOn are characterized by powder X-ray diffraction （PXRD）, scanning electron microscopy, energydispersive spectroscopy, fourier transform infrared spectroscopy and UV-visible diffuse reflectance spectroscopy. Both samples are found to crystallize in a monoclinic lattice with cc space group. The d-lines of KSbPO and KSbPOn are refined by least square fitting the PXRD data, using POWD software to obtain their unit cell parameters. The bandgap energy （Eg） of both pristine and n-doped KSbPO is found from their Kubelka-Munk plot. The KSbPOn/visible photocatalytic degradation of methylene blue and rhodamine B has been investigated in aqueous heterogeneous suspension. The generation of .OH in the presence of KSbPOn during the photoreaction is verified by a fluorescence technique using terephthalic acid （TA） as a probe.

关键词： Potassium phosphatoantimonates characterization Organic dyes Photodegradation

Polygeneration Study of Low-to-Medium Enthalpy Geothermal Reservoirs in Mexico

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Journal of Thermal Science 2021年第3期30卷 1077-1087页

作者： chÁVEZ Oscar GODÍnEZ francisco Tecnológico nacional de México/I.T.chihuahua.Av.Tecnológico 2909 C.P.31310ChihuahuaChihuahuaMéxico Instituto de Ingeniería Universidad Nacional Autónoma de MéxicoUNAMC.U.Ciudad de MéxicoC.P.04510México Polo Universitario de Tecnología Avanzada Universidad Nacional Autónoma de MéxicoVía de la Innovación No.410Autopista Monterrey-Aeropuertokm.10 PIITC.P.66629Apodaca Nuevo LeónMéxico

This study combines the thermodynamic analysis of a polygeneration system along with the numerical modelling of the thermal behavior of geothermal reservoirs in Mexico to exploit their *** reservoir was modeled as a porous medium assuming a five-spot well configuration and local thermal *** heat conduction-convection along with the Laplace equations were solved to compute temperature distributions,the useful life and the optimum distance between injection-extraction *** predicted temperature and pressure of the geothermal fluid at the outlet of the reservoir were exploited in the polygeneration system consisting of:(1)a Rankine cycle,(2)an absorption refrigeration cycle,and(3)a heat *** developed approach allows calculating both the optimal distance between injection-extraction wells and the global(utilization)efficiency of six arrangements(each composed by a reservoir connected to a polygeneration system)by assuming that reservoirs have a lifespan of 30 *** also show that:(a)due to the low efficiency of the Rankine cycle,very little thermal energy is converted into electrical one;(b)not only the temperature and the size are important when evaluating the power production performance of reservoirs,but also the permeability plays a fundamental role;(c)the first law efficiency of the polygeneration system ranges from 41.9%to 43.7%;(d)the utilization efficiency of the six arrangements lies in the range between 25.8%and 31%.

关键词： polygeneration system geothermal reservoir local thermal equilibrium low-to-medium enthalpy